Such a panel is for example known from U.S. Pat. No. 5,912,444, which discloses an interlock between a door of a housing and a circuit breaker. In this publication a mechanism is explained, which allows for racking the circuit breaker only from the disconnected position into the service position, when the door is closed.
Draw-out devices, such as a vacuum circuit breaker, are typically provided with secondary plugs, which also need to be connected in the panel for a proper functioning of the draw-out device. The secondary plugs could for example provide connections with sensors in the draw-out device for monitoring the status of the draw-out device.
However, known panels, such as described in U.S. Pat. No. 5,912,444, still allow for the draw-out device to be racked into the service position without the secondary plugs being connected. So, the draw-out device can be taken into use, without being properly connected. This is undesired.